Paras Hospital Gurgaon — Excess charge of surgery for government employee in education department

I undergone with a surgery .MY mom is a government employee and she told at billing counter or staff present at their when i was admitted in emergency ward. But no one take serious her at that moment and they make excess amount of bill . when my mom submitted that bill in the department then department told that the bill amount is very high as compared they have to charge. now i went to the hospital to revise the bill as govt. employee then they deny to do so...